✨🧪♻️➕ vanth, vanth_derive: Add derive macro for Vanth trait implementation

- Added `vanth_derive` crate with a procedural macro to automatically implement the `Vanth` trait for structs, including generics.
- Refactored `vanth` crate by removing obsolete `vanth.rs` file.
- Implemented `PartialEq` for `Ty` to enable comparisons with string values and another `Ty`.
- Added integration tests for deriving `Vanth` with generic parameters.
- Updated dependencies: added `quote`, `syn`, and `proc-macro2` crates.

Cargo.lock

@@ -1009,6 +1009,7 @@ dependencies = [
  "digest",
  "serde",
  "serde_json",
+ "vanth_derive",
 ]
 
 [[package]]
@@ -1019,6 +1020,15 @@ dependencies = [
  "vanth",
 ]
 
+[[package]]
+name = "vanth_derive"
+version = "0.1.0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "variadics_please"
 version = "1.1.0"

Cargo.toml

@@ -15,3 +15,6 @@ serde = { version = "1.0.219", features = ["derive"] }
 serde_json = "1.0.140"
 digest = "0.10.7"
 blake3 = { version = "1.8.2", features = ["traits-preview"] }
+quote = "1.0"
+syn = { version = "2.0", features = ["full"] }
+proc-macro2 = "1.0"

crates/vanth/Cargo.toml

@@ -13,3 +13,4 @@ digest.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 blake3.workspace = true
+vanth_derive = { path = "../vanth_derive" }

crates/vanth/src/lib.rs

@@ -12,6 +12,7 @@ pub mod entity;
 pub mod hashing_serializer;
 
 pub use hashing_serializer::hash;
+pub use vanth_derive::Vanth;
 
 pub type Result<T> = std::result::Result<T, Error>;
 
@@ -77,10 +78,22 @@ pub struct Value {
 
 #[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct Ty {
-    path: Vec<String>,
+    pub path: Vec<String>,
 }
 
-pub trait Vanth: Serialize + DeserializeOwned {
+impl PartialEq for Ty {
+    fn eq(&self, other: &Self) -> bool {
+        self.path == other.path
+    }
+}
+
+impl <T: AsRef<str>> PartialEq<T> for Ty {
+    fn eq(&self, other: &T) -> bool {
+        self.path.join("::") == *other.as_ref()
+    }
+}
+
+pub trait Vanth {
     fn ty() -> Ty;
 }
 

crates/vanth/src/vanth.rs

@@ -1,18 +0,0 @@
-#![allow(unused)]
-
-use std::path::PathBuf;
-
-pub struct Value {}
-
-pub struct Ty {}
-
-pub enum Primitive {
-    Bool(bool),
-    Int(i32),
-    Float(f32),
-    String(String),
-    Path(PathBuf),
-    Char(char),
-    Byte(u8),
-    ByteArray(Vec<u8>),
-}

crates/vanth/tests/integration/derive.rs

@@ -1,5 +1,5 @@
 use bevy_ecs::component::Component;
-use serde::{Deserialize, Serialize};
+use serde::{de::DeserializeOwned, Deserialize, Serialize};
 use vanth::Vanth;
 
 // TODO: derive `Vanth`
@@ -10,5 +10,29 @@ struct Foo {
 
 #[test]
 fn test_derive() {
-    println!("yeet");
+    #[derive(Deserialize, Serialize, Vanth)]
+    struct Foo<T: Vanth> {
+        field_a: i32,
+        field_b: String,
+        inner: T,
+    }
+    
+    #[derive(Deserialize, Serialize, Vanth)]
+    struct Bar {
+        field_a: i32,
+    }
+    
+    #[derive(Deserialize, Serialize, Vanth)]
+    struct Qux<T: Vanth, S: Vanth> {
+        field_a: i32,
+        field_b: String,
+        inner: T,
+        inner_2: S,
+    }
+    
+    let base = "integration::derive::";
+    
+    assert_eq!(Bar::ty(), format!("{base}Bar"));
+    assert_eq!(Foo::<Bar>::ty(), format!("{base}Foo<{base}Bar>"));
+    assert_eq!(Qux::<Bar, Foo<Bar>>::ty(), format!("{base}Qux<{base}Bar,{base}Foo<{base}Bar>>"));
 }

crates/vanth_derive/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "vanth_derive"
+version.workspace = true
+edition.workspace = true
+
+[lib]
+proc-macro = true
+
+[dependencies]
+quote.workspace = true
+syn.workspace = true
+proc-macro2.workspace = true

crates/vanth_derive/src/lib.rs

@@ -0,0 +1,51 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{parse_macro_input, DeriveInput, GenericParam, Generics};
+use syn::parse_quote;
+
+#[proc_macro_derive(Vanth)]
+pub fn vanth_derive(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+
+    let name = input.ident.clone();
+
+    let mut generics = input.generics.clone();
+
+    let type_params: Vec<syn::Ident> = generics.params.iter().filter_map(|param| {
+        if let GenericParam::Type(type_param) = param {
+            Some(type_param.ident.clone())
+        } else {
+            None
+        }
+    }).collect();
+
+    let mut where_clause = generics.where_clause.clone().unwrap_or_else(|| parse_quote!(where ));
+    for tp in &type_params {
+        where_clause.predicates.push(parse_quote!(#tp : vanth::Vanth));
+    }
+
+    let (impl_generics, ty_generics, _) = generics.split_for_impl();
+
+    let generics_code = if type_params.is_empty() {
+        quote! { String::new() }
+    } else {
+        quote! {
+            format!("<{}>", [#(#type_params::ty().path.join("::")),*].join(","))
+        }
+    };
+
+    let expanded = quote! {
+        impl #impl_generics vanth::Vanth for #name #ty_generics #where_clause {
+            fn ty() -> vanth::Ty {
+                let module_path = module_path!();
+                let mut path: Vec<String> = module_path.split("::").map(|s| s.to_string()).collect();
+                let base_name = stringify!(#name);
+                let generics_str = #generics_code;
+                path.push(format!("{}{}", base_name, generics_str));
+                vanth::Ty { path }
+            }
+        }
+    };
+
+    TokenStream::from(expanded)
+}